Larval Eels Disappear Like a Wisp of Smoke in Bali

November 10, 2011

In Bali, what many may dismiss as a current in the water may actually be an eel in its larval stage. Recently, divers captured footage of the Leptocephalus, which is the name for any eel in its larval stage. It is Latin for "slim head," because the head of this swimmer is the only part of it that is clearly visible.

Wide, transparent and ribbon-like, these larval eels literally pack on substance as they swim to what will be their permanent homes from the at-sea breeding grounds of their parents, according to Wired Science. Because they lack red blood cells during their larval stage, the eels have small organs with transparent internal tissues. Their appearance makes them invisible to predators, which often includes humans. However, those looking for this type of nature travel may be able to see grown eels on a Bali tour[1].

Eels have been cloaked in misunderstanding since Aristotle's declaration that they emerged from the dropping of earthworms. The creatures were recognized as fish in the late 18th century, and the Leptocephalus was only discovered to be a larval version of a regular eel in the late 19th century — it was previously thought to be its own species.